Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
su sach » so sach, vu sach
xanh di » danh di, vanh dai, xanh tai
xa xanh » xa thanh, cay xanh, mau xanh
thuc xa » thuc xay, tuc xa, thuc va
sach va » sach xa, sach ha, sach dao
hieu va » hieu qua
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
di cua » dai cua, doi cua, de cua
cua su » qua su

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach va ((nang ma) or (sang ma)) hoi. ((hieu va) OR (lieu va)) nham thuc xa xanh di cua su~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach va ((nang ma) OR (sang ma)) hoi. ((hieu va) OR (lieu va)) nham thuc xa xanh di cua su*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach va ((nang ma) or (sang ma)) hoi. ((hieu va) OR (lieu va)) nham thuc xa xanh di cua su*".